HackerEarth Rotation problem solution YASH PAL, 31 July 202417 February 2026 In this HackerEarth Rotation problem solution You are given two strings S and T of the same length N. Your task is to convert the string S into T by doing some operations. In an operation, you can delete the first character of the string S and append any character at the end of the string. You are required to determine the minimum number of operations to convert S into T. HackerEarth Rotation problem solution.#include<bits/stdc++.h>using namespace std;#define ll long long#define mod 1000000007ll#define vll vector<ll>#define pll pair<ll,ll>#define vpll vector<pll>#define pb push_back#define mp make_pair#define x first#define y secondll lps[1000005], match[1000005], n;string s, t;void com_lps(){ ll j = 0, i = 1; lps[0] = 0; while(i < n) { if(s[i] == s[j]) { j ++; lps[i] = j; i ++; } else { if(j) j = lps[j - 1]; else { lps[i] = 0; i ++; } } }}ll solve(){ memset(match, 0, sizeof(match)); ll i = 0, j = 0; while(i < n) { if(t[j] == s[i]) { j ++; match[i] = j; i ++; if(j == n) return 0; } else { if(j) j = lps[j - 1]; else i ++; } } return n - match[n - 1];}int main(){// freopen("inp.txt", "r", stdin);// freopen("out.txt", "w", stdout); cin >> n; cin >> s; cin >> t; com_lps(); cout << solve();// fclose(stdin);// fclose(stdout); return 0;} Second solution#include <bits/stdc++.h>using namespace std;typedef long long ll;const int maxn = 1e7 + 17;int main(){ ios::sync_with_stdio(0), cin.tie(0); int n; cin >> n; string s, p; cin >> s >> p; reverse(s.begin(), s.end()); for(int i = 0; ; i++){ if(string(s.rbegin(), s.rend()) == p) return cout << i << 'n', 0; s.pop_back(); p.pop_back(); }} coding problems solutions HackerEarth HackerEarth